Zero printing control for tabulators



Dec. 23, 1952 w. wocKENFUss ZERO PRINTING CONTROL FOR TABULATORS Original Filed March 4, 1948 VCV Patented Dec. 23, 1952 ZERO PRINTING CONTROL FOR TABULATORS William Wockenfuss, Union, N. J., assignor, by

mesne assignments, to Burroughs Adding Machine Company, a corporation of Michigan Original application March 4, 194.8, Serial No. 13,017. Divided and this application July 15, 1949, Serial No. 104,985

4 Claims.

This invention relates to improvements in :printing mechanisms for tabulators and has particular reference to a control means therefor, the present disclosure being a `division of my copending `application Serial No. 13,017, filed March 4, 1948, now Patent No. 2,562, 250.

An object of this invention is t-o provide an improved control mechanism for the print hammers of a tabulator, which mechanism is of simple land practical construction and by means of which the operati-on and locking out of said harnmers and the elimination of zeros to the left and right of `signiiic'ant gures may be -eiiectively accomplished.

The above and other objects will 'appear more clearly from the following detailed description when taken in connection with the accompanying drawing which illustrates a preferred embodiment of the inventive idea; but it is to be expressly understood that said drawing is employed merely for the .purpose of facilitating the description of the invention as a whole and not to Idenne the limits thereof, reference being had to the appended claims for this purpose.

In the drawing:

Fig. l is `a fragmentary sectional View through the print control mechanism of a tabulator constructed in `accordance with the invention; and

Fig. 2 is a fragmentary top plan view thereof, partly broken away and shown in section.

The control unit of the present invention operates in conjunction with the type bars |41 and printing is accomplished by a ring pin 484 for each type bar, with said pin operated to strike an Ialigne-d type 485 `after the tylpe bar has been elevated to printing position, and when the lassociated hammer 1188 is released and thereupon propelled by its actuating spring 481, thus causing the aligned type 465 to print upon -a record sheet lcarried on the platen 468. The hammers 456 are mounted to swing about the shaft 489 and, after :performing a printing operation, are restored by the common hail 410 operated from the shaft l18a, as described in the above identied application. Said shaft also controls rock shaft 416 which, through its bell cranks 411, lactuates the reciprocatory hammer release bail 418 to release the hammers at the moment the type bars |41 have reached their printing position. The bail 111.8 is t. ereafter restored by the springs 419 connected to the bell cranks dll.

To accomplish the release of the hammers, each has 'associated therewith a rockingly supported and vertically movable interposer 488 which, in the position of Fig. l, is inoperative and permits the bail 418 to pass beneath the shoulder formed by the reduced lower end of the interposer so that the hammer 468 will not be released 'With the type bar in the blank Iposition shown. However, should the type bar move upwardly and be arrested to align its uppermost or 0 type with the pin 464, this movement Apermits the lever 48| the rear end of which engages under a shoulder on said bar, to turn clockwise one step under the influence of the spring 482 connecting the same with its interposer 488. The forward end of said lever has a pin and slot connection with the interposer so that said movement will -pull the latter downwardly to project its left edge of the enlarged portion thereof into the path of the bail 418. With the parts in the 0 printing position, the projection 483 on the interposer will, upon said downward movement, still be in -alignment with the rear extremity of the zero eliminati-on control lever 481% in its intermedate position. Said lever is pivoted to the hammer release plate 485 who-se rear extremity `48B engages the hammer 485 to hold it in inoperative or restored position. With said lever rand plate secured together by the pivotal connection therebetween, it will now be apparent that upon operation of the bail 418, the interposer 1488 will be moved forwardly and its projection 483 will contact the rear extremity of the lever 484 to impart a similar movement to the latter and to said plate 485 to retract the end 486 of the latter from the hammer and thus permit it to fire and print va zero. Immediately thereafter, the bail 41B is retracted by the springs 419, the bail 410 restores the hammers 455 and, upon ydownward movement of the type bar, the lever 48| is rocked Icounterclockwise to lift the inter-poser 480 to its inoperative position, with the bail 481 attached to the bail 418 acting to restore the plate 485 land lever l4&4 so that the extremity 48S of said plate will `again engage the hammer l488. `Springs 488 connected 4to the plates 485 also aid in restoring them to hammer locking position.

Should the type bar, in its upward movement, be arrested in position to print a l or a digit of higher order, the upward movement of said bar will permit the lever @8| to move an additional step which will lower the interposer 480 sufciently to 4align its projection `403 with 1a ,projection 488 on the plate 485 so that forward movement of the interposer under the influence of the bail 481 will cause the plate 485 to `assume its hammer releasing position and, incidentally, carry its lever 484 with it.

Zero elimination to the left or right is accomplished by, respectively, depressing or raising the front ends of the levers 484 from their intermediate positions, and said levers are all frictionally held in their three adjusted positions by the spring latches 498. When eliminating to the left in any group of columns to which a set of type bars is assigned, all levers 484 individual to said columns are depressed and, in so doing, the inner extremities of said levers will be elevated so that when the bail 418 is advanced to actuate the interposers 488 the projections 483 thereon will enter the spaces between said extremities and the projections 489 on the plates 485, and the latter will not, therefore, be advanced to release their respective hammers 488. However, a significant ligure in any one of said columns will be printed because, in that case, the interposer 488 will be lowered to its second step, as previously described, and the projection 483 thereon will be aligned with the projection 489, thus causing the plate 485 to be advanced when the interposer is operated. The appearance of a significant figure in any one of said columns results in a zero being printed in the column or columns to the right of the first named column in which the zero would have otherwise been eliminated. This is accomplished by providing each of the levers 484 with a laterally offset and forwardly extending lug 49| projecting through and to the right of the plate 485 on which said lever is pivoted. When said lever is depressed, said lug 49| will be horizontally aligned with a rearwardly extending lug 492 formed on the plate to the right of said lever and offset to the left of said plate. Consequently, as the plate 485 individual to the signiiicant figure to be printed is advanced to release its hammer, the lug 49| of the lever carried by said plate will contact the lug 492 on the plate to the right and thereby also advance the latter plate which will then release its hammer to print a zero. In the same manner, any other plate to the right of the last named plate which would normally eliminate the printing of a zero because of the depression of its ever, would be advanced, due to the presence of the mentioned significant figure, by engagement of its lug 492 with the lug 49| of the lever carried by said last named plate, and a zero would therefore be printed because of the consequent advancement of said other plate.

Zero elimination to the right is eifected by raising the levers 484 individual to the columns in which such elimination is to occur. This adjustment of the levers lowers their rear or inner extremities so that they are now positioned in overlapping relation to the projections 489 of their respective plates. When so located, the projections 483 on the associated interposers 488 will pass over the inner ends of said levers when the interposers have been lowered only one step by the levers 48| and then advanced by the bail 418. Therefore, each projection 483 will fail to engage either its lever 484 or its plate 485 and the latter will not be moved forwardly to release its hammer. When a significant figure is to be printed in one of said columns, the interposer 488 individual thereto is lowered sufficiently by the lever 48| to allow its projection 483 to align with the projection 489 on the associated plate 485 so that the latter will be operated to release its hammer when the bail 418 is advanced to actuate said interposer. The lever 484 of the plate which controls the printing of said signicant gure eiects the printing of a zero in the column to the left by means of the forwardly extending lug 493 on said lever, which lug is oiset tot the Opposite side .4 of the lever from the lug 49| thereon. Said lug 493, under the condition being described,is aligned with a rearwardly extending lug 494 on the plate 485 to the left of said lever and said lug 494 is offset in the opposite direction from the lug 492 on said plate and will therefore be horizontally aligned with said lug 493. Hence, when the plate which controls the printing of said significant figure is actuated to release its hammer, said lug 493 of the lever attached to said plate will engage said lug 494 on the plate to the left and operate the latter to also release its hammer so that a zero will be printed to the left of the signficant figure. In a manner which will now be understood, a zero will be printed in any other column of the group under consideration which is to the left of that just described, by reason of the fact that the lug 493 of the lever to the right will engage the lug 494 of the plate individual to said other column and thus actuate said plate to release its hammer.

The operation of locking out a hammer 488 occurs at the beginning of a listing cycle and before the type bars start their upward movement, and is effected by preventing downward movement of the associated interposer 488 which has been restored to the position of Fig. 1 at the conclusion of the previous cycle when the associated type bar depressed the adjacent end of the lever 48|. Under this condition, the bail 418, when advanced, will pass under the shoulder formed in the adjacent edge of the interposer and will not operate the latter. To lock up the interposer, there is provided a detent 495 normally held in its inoperative position by the spring 496 so that its rear end will be held out of the path of the shoulder formed by the recess 491 in the adjacent edge of the interposer. A lock-out key 498 for each detent is free to turn on an oscillatory bail 499 and as the latter is swung to the left, as viewed in Fig. 1, and the key 498 is in its inoperative position as shown, a pin 588 on said key will ride over the upper edge of the detent and will not, therefore, urge the same rearwardly. However, when the key is pre-set by pushing it rearwardly about the bail 499 to engage the pin 588 in the notch 58| of the detent and said bail is then swung rearwardly at the beginning of the operating cycle, the rear end of the detent will enter the recess 491 to engage the mentioned shoulder formed thereby, and the interposer will therefore be held in itsv raised position and its associated hammer will not be red. The bail 499 is operated from a rock shaft 582 to which it is connected by links 583 at opposite ends of the bail and the rocking action of said shaft is fully disclosed in said co-pending application.

What is claimed is:

l. In a printing mechanism for tabulators, a plurality of type hammers, a release plate for each hammer, an operating bail common to said plates, an interposer for each plate having a normally inoperative position relative to said bail and having means thereon coacting with a portion of said plate to move the same to a release position with respect to its hammer when said interposer is moved from its normal position, said interposer further having a recess therein, an operating member for said interposer operable to move the same from its normal position into operative association with said bail, a normally inactive locking detent for each interposer, an oscillatory bail associated with said detents, a key for each detent mounted on said oscillatory bail and settable with respect thereto to render said detent operative and having means thereon to actuate said detent when said oscillatory bail is operated to engage said detent in the recess of said interposer to lock the same against movement by said operating member.

2. In a printing mechanism for tabulators, a plurality of type hammers, a release plate for each hammer, a Zero elimination control lever pivoted to each plate and having an intermediate and two eliminating positions, an interposer for each release plate having means thereon adapted for engagement with said lever` when the latter is in intermediate position, means to operate said interposer to engage its means with said lever to thereby operate said release plate, and means formed on said plate and lever coacting when the latter is in either of its two eliminating positions to operate the next adjacent release plate when said interposer is operated to release its hammer to print a significant ligure.

3. In a printing mechanism for tabulators, a plurality of type hammers, a movable type bar with which each hammer cooperates, adjacent release plates for said hammers, a Zero elimination control lever carried by each release plate and movable relative thereto from an intermediate position to diierent eliminating positions, an interposer for each release plate adapted for engagement with its lever in the intermediate position thereof, means controlled by a movement of a type bar for adjusting said interposer into position for engagement with its lever, means to operate said interposer so as to actuate said lever and the release plate carrying the same, and means on said plates and levers coacting When one of the latter is in an eliminating position to operate the next adjacent release plate when an 6 interposer is operated to release its hammer to print a significant figure.

4. In a printing mechanism for tabulators, a plurality of type bars movable from restored to printing positions, a hammer for each type bar, releasable means for retaining said hammer inoperative, an operating bail, interposers coacting with said releasable means and operated by said bail to release said means, said interposers having normally inoperative positions relative to said bail, means operatively connecting each type bar with an interposer for adjusting the latter to operative position relative to said bail for operation thereby when said type bar is moved from its restored to printing position, a locking detent for each interposer, a second bail operatively associated with said detents, an operating element for each detent carried by said second bail and having operative and inoperative positions relative to said detent, and operating means for said second bail operable, when an interposer is in its inoperative position, to actuate its associated operative detent to lock said interposer against movement to its operative position relative to the first named bail.

WILLIAM WOCKENFUSS.

REFERENCES CTED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,946,900 Daly Feb. 13, 1934 2,131,918 Mills Oct. 4, 1938 2,307,635 Mueller Jan. 5, 1943 2,387,861 Smith Oct. 30, 1945 

